Concrete poured wall foundations are becoming increasing popular in new construction practices. Poured walls provide certain well known advantages over concrete block construction. Removable forms are now frequently being used to form poured concrete walls of basements or buildings. Such forms are frequently used repeatedly and must withstand substantial wear and abuse during handling and shipping. Concrete construction forms must also be very rigid to avoid bending when subjected to static pressure generated by the concrete when it is poured between the forms.
To accommodate the requirements that such forms be durable and resistant to bending, prior art forms have generally been constructed from steel, iron, wood or aluminum. Such forms have the disadvantage that they are relatively heavy and difficult to manipulate. Consequently, handling of the forms becomes time consuming and labor intensive, and concrete casting comprises a substantial part of the cost of building construction. Additionally, most prior art systems require some form of forming oil or lubricant which decreases the tendency of the form face sheet to stick to the poured concrete wall. Forming oil or lubricant management is often a disadvantage to the use of poured wall foundations.
Current concrete forms are also expensive to manufacture as they require multiple parts such as many as seven to ten ladder supports which are required to support the concrete form. Further, current concrete form designs are not conducive to maintenance or repair as they do have include interchangeable long lasting parts. If a side rail or ladder is broken or unfit for use, the entire concrete form is discarded.
U.S. Pat. No. 4,150,808 to Robert D. Sawyer discloses a removable form for use in pouring concrete walls, the form being comprised of a high strength, impact resistant, light weight material and being constructed to provide thermal insulation of concrete poured between two of the forms. The forms are each comprised of a face plate backed by an insulative support structure. The insulative support structure has a honeycomb construction filled with an insulative material, the honeycomb construction providing strength to the insulative support structure to prevent bending or distortion. A supporting frame is further provided as a structural supporting backing for the insulative support section to increase its resistance to bending.